A Spad Array Level Readout Circuit Using Quadratic Correlation Double Sampling Technology

A correlated double sampling and readout circuit technology, which is applied to TV, electrical components, color TV, etc., can solve the problems of complex timing signals, ineffective operation, large integral capacitance, etc., to improve work efficiency, reduce production costs, read fast effect
CN108391071BActive Publication Date: 2020-04-14NANJING UNIV OF POSTS & TELECOMM +1

Patent Information

Authority / Receiving Office
CN Β· China
Patent Type
Patents(China)
Current Assignee / Owner
NANJING UNIV OF POSTS & TELECOMM
Publication Date
2020-04-14

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a SPAD array-level readout circuit adopting quadratic correlation double-sampling technology, which includes a CDS readout circuit and a sample-and-hold circuit. The first-stage CDS readout circuit consists of a voltage follower, two switch circuits and a sampling capacitor, which are connected to each column bus to ensure fast readout of the information of the pixel unit, and the information in the pixel unit Fixed pattern noise cancellation. The second-stage CDS readout circuit consists of 2 voltage followers, 2 switch circuits and 2 sampling capacitors, which are used to eliminate fixed pattern noise in the readout circuit. The quadratic correlation double-sampling array-level readout circuit only needs two control signals, and the timing signal is simple. The invention has the advantages of simple timing control and fast readout speed. The two-stage CDS only needs two control signals, and the readout speed is fast, which improves the working efficiency of the readout circuit. Therefore, it has obvious advantages in large-scale pixel array circuits.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the field of optoelectronic technology, and relates to a correlated double sampling noise reduction readout circuit applied to a high-density single-photon avalanche diode array detector. Background technique

[0002] Single-photon avalanche diodes (SPADs) have a wide range of applications in technical fields such as fluorescence lifetime imaging, Raman spectroscopy, and 3D imaging due to their high sensitivity and sub-second temporal resolution. At present, single-photon avalanche diodes are developing in the direction of low-cost, high-density, high-reliability deep-submicron CMOS process array image sensors. A SPAD array detector includes numerous SPAD pixel units and peripheral readout and control circuits, wherein each SPAD pixel unit is composed of a SPAD device, a quench reset circuit and a count readout circuit. The pixel readout voltage value measured by the analog counting method can reflect the number of detected ph...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More